Member Avatar for mith_cool

I have designed a jsp which has the following code :

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">

<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>Form Cookie</title>
    </head>
    <body>
        <form action="http://localhost:8080/FormCookie/AddValue">
            Name : <input type="text" name="name"><br>
            Age : <input type="text" name="age">
            <input type="submit" value="submit">
        </form>
    </body>
</html>

Secondly i created a servlet which retrieves the name and age that user enters and stores it in the cookie. hers the code

protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        String name= request.getParameter("name");
        String age= request.getParameter("age");
        Cookie c= new Cookie("myname", name);
        Cookie c1= new Cookie("age", age);
        response.addCookie(c);
        response.addCookie(c1);
        c.setMaxAge(20);
        c1.setMaxAge(20);
    }

and finally i created a servlet which simply prints the values stored in the cookie file

protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
       Cookie[] cookie = request.getCookies();
       response.setContentType("text/html");
       PrintWriter out = response.getWriter();
       for(int i=0; i<cookie.length;i++)
       {
          
           if(cookie==null)
          {
              out.println("No cookie found");
          }
           else if(cookie[i].getName().equals("myname"))
          {
              out.println("Name is "+cookie[i].getValue());
          }
          else if(cookie[i].getName().equals("age"))
          {
              out.println("age is "+cookie[i].getValue());
          }
           }
           
      
       out.close();

    }

Now there is nowhere problem in printing the values of the cookie file infact this code works well but when i close up my browser am unable to get that values stored in the cookie file and also it gives me nullpointerxception though i have used a if condition specifying (c==null){ blah blah }. so i just want to know why am not getting printed in the browser "no cookie found" and also when i close my browser and open it for the next time, i should be able to get the value stored in the cookie......

Edited by mith_cool because: n/a
  • 2 Contributors
  • 2 Replies
  • 90 Views
  • 1 Day Discussion Span
  • Latest Post Latest Post by mith_cool
Member Avatar for ~s.o.s~

also it gives me nullpointerxception though i have used a if condition specifying (c==null)

This is because the condition is executed after the length check of the for loop. The condition cookie == null needs to be placed outside the FOR loop and not inside it.

when i close my browser and open it for the next time, i should be able to get the value stored in the cookie

Set the maxAge of the cookie accordingly. Have you looked at the docs for the setMaxAge method? It says that the cookie is persisted for the number of seconds you pass in to the setMaxAge method which in your case is only 20. Set it to something higher like 60 * 60 * 24 for persisting the cookie for an entire day.

Member Avatar for mith_cool

Thanx sir. It now actually worked and also thanx for rectifying my silly mistake of placing cookie==null inside the loop.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.